Using Polygon group editor to reduce materials (SOLVED)

Hi
I am having trouble understanding how to properly reduce the amount of materials on a daz figure, for use in Unity. I create a new surface (eg. Character skin), and assign other surfaces to this one. However, when I do this, my figure turns grey. If I export it as .fbx to Unity, it does have one material, but loses uv assignments. When I attach the texture atlas image,(that I Captured before surface assignment), it just appears all over.
Any help would be appreciated.
Thanks

Can someone guide me to how I can reduce the number of polygon groups using the Polygon Group Editor? (I have a shirt with 4 surfaces, they all reference the same texture, I just want to make that 1 surface for the shirt and therefore 1 drawcall/material in Unity or UE4).